There's nasty court cases like that every day in the courts with the current system. That's no reason to NOT change things.
you'll instead have a nasty court battle with the sibling arguing "they hated each other" and the partner arguing "we loved each other."
There's nasty court cases like that every day in the courts with the current system. That's no reason to change things.
No, actually I don't.
In your example there's not enough info to determine if the person who died (wasn't me, I have a will that sets out explicitly what I want done with my estate) wanted either the sibling or the romantic partner to get all or part of the money. Maybe the person was on the verge of breaking up with the partner. Maybe the partner is independently wealthy and the sibling has more need of the money. Maybe the sibling has children. Maybe the person wanted to leave all the money to her favourite charity.
Regardless, I don't see how the government getting out of marriage affects the outcome in this case.